The present invention relates to an apparatus for controlling an a. c. motor and a module using the same.
A study paper “Development of full automatic washing machine which is controlled by an inverter” reported in research meeting at Ibaraki Office of Tokyo Branch, The Institute of Electrical Engineers of Japan (IEEJ) (1999) describes “an open loop type vector control scheme” is utilized in an electric motor current sensorless, low resolution position detector.
Another prior art using a magnetic pole position detector and an electric motor current sensor is disclosed in JP-A-2000-324881 which teaches a control device. In this device an electric current detector directly detects currents flowing through windings of a motor for generating such a voltage instruction that an instructed current is equal to detected currents in a rotary coordinate system.